The Organic Growth of Portland's Green Roofs

Portland’s ecoroof program is enough to turn other sustainability-striving cities green with envy. The City of Roses boasts 351 green roofs and rooftop gardens covering more than 26 acres.* By comparison, Seattle has 62 vegetated roofs totaling about 9 acres.

How’d they do it?

I had the opportunity to talk to Amy Chomowicz, one of the city’s top ecoroof officials, for a story that’s out today on the Seattle P-I’s website and got the skinny.

Turns out that the roots of Portland’s ecoroofs can really be traced back to one guy: Tom Liptan.

Here’s the story.

Back in the mid 1980s a colleague of Chomowicz and Liptan went to France and stumbled upon a book from a British publisher called “Building Green,” which included info on ecoroofs. Liptan was impressed with the book, Chomowicz said, and bought a bunch of them for his city of Portland coworkers.

(As we were talking, Chomowicz was able to still dig her copy off her desk in the Bureau of Environmental Services.)

Ecoroofs are touted for their ability to trap and hold rainwater that would otherwise pour onto streets or into gutters, carrying pollution and potentially causing sewer overflows, flooding, and stream erosion. The roofs can insulate buildings, cutting heating and cooling costs; provide green spaces for people, birds, and bugs; reduce heat island effects; and even lengthen the life of a roof.

Liptan was so captivated, that in 1996 he built Portland’s first known ecoroof on top of his garage. He’s tinkered with it over the years and the roof and garage are still standing. That was the beginning of city’s program, Chomowicz said.

The effort got a huge boost when Portland Mayor Sam Adams earmarked $6 million for an incentive program that’s putting ecoroofs on private buildings all across town. The 2-year-old Grey to Green program already has awarded $1.3 million for the construction of 6 acres of new roofs. The program is slated to last until 2013.

All of this investment and attention has helped drive down the cost of ecoroofs and increased the number of ecoroof vendors, said Sarah Reich, a policy analyst with ECONorwest, an economic consulting firm.

An ecoroof industry group has even formed in Portland called the Green Roof Information Think Tank (GRIT). It’s a forum for sharing green roof issues, opportunities, challenges, news, and strategies. On top of that, the city maintains a great ecoroof blog of its own.

It’s a pretty interesting example of how one guy’s curiosity and experimentation grew organically into a city’s widespread commitment to an innovative, sustainable building practice.

As I report in the P-I, Seattle leaders want to jump start this city’s ecoroof construction, and is trying to do so by making sure it understands the costs and benefits of these projects. City leaders today are releasing a new report inventorying Seattle’s green roofs, and publishing a walking tour of vegetated roofs around the city. Now they just need to find their Tom Liptan.

* Portland’s green roof stats were supplied by Amy Chomowicz in an email and interview.